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Objectives: We perform a comparative assessment of shape variation of the proximal fibula in extant humans and great apes, intending to investigate the possible link between proximal fibular shape and locomotor patterns. Methods: Our sample includes 94 fibulae of 37 Homo sapiens, 15 Gorilla, 17 Pongo, and 25 Pan. Fibular morphology was investigated through three‐dimensional (semi)landmark‐based geometric morphometric methods. Results: We found unique features of the human fibular head compared to that of great apes (i.e., oblique articular surface, the presence of the styloid process, specific morphology of muscle attachment sites), supporting the functional role of this bone in relation to human obligate bipedalism. Great apes also showed distinctive traits in their proximal fibula morphology, in agreement with differences in locomotor behavior. Conclusion: The morphology of the proximal fibula in extant humans and great apes is indicative of locomotor behavior, offering the potential for the comparative analysis of fossil hominin remains. [ABSTRACT FROM AUTHOR]

Objectives: Despite the longstanding importance of grasping adaptations in theories of primate evolution, quantitative data on primate grasping strength remain rare. We present the results of two studies testing the prediction that callitrichines—given their comparative retreat from a small‐branch environment and specialization for movement and foraging on tree trunks and large boughs—should be characterized by weaker grasping forces and underdeveloped digital flexor muscles relative to other platyrrhines. Methods: First, we directly measured manual grasping strength in marmosets (Callithrix jacchus) and squirrel monkeys (Saimiri boliviensis), using a custom‐constructed force transducer. Second, we reanalyzed existing datasets on the fiber architecture of forearm and leg muscles in 12 platyrrhine species, quantifying digital flexor muscle physiological cross‐sectional area (i.e., PCSA, a morphometric proxy of muscle strength) relative to the summed PCSA across all forearm or leg muscles. Results: Callithrix was characterized by lower mean and maximum grasping forces than Saimiri, and callitrichines as a clade were found to have relatively underdeveloped manual digital flexor muscle PCSA. However, relative pedal digital flexor PCSA did not significantly differ between callitrichines and other platyrrhines. Conclusions: We found partial support for the hypothesis that variation in predominant substrate usage explains variation in empirical measurements of and morphological correlates of grasping strength in platyrrhines. Future research should extend the work presented here by (1) collecting morphological and empirical metrics of grasping strength in additional primate taxa and (2) extending performance testing to include empirical measures of primate pedal grasping forces as well. [ABSTRACT FROM AUTHOR]

This study proposes a new way to use metatarsals to identify locomotor behavior of fossil hominins. Metatarsal head articular dimensions and diaphyseal strength in a sample of chimpanzees, gorillas, orangutans, and humans (n = 76) are used to explore the relationships of these parameters with different locomotor modes. Results show that ratios between metatarsal head articular proportions and diaphyseal strength of the hallucal and fifth metatarsal discriminate among extant great apes and humans based on their different locomotor modes. In particular, the hallucal and fifth metatarsal characteristics of humans are functionally related to the different ranges of motion and load patterns during stance phase in the forefoot of humans in bipedal locomotion. This method may be applicable to isolated fossil hominin metatarsals to provide new information relevant to debates regarding the evolution of human bipedal locomotion. The second to fourth metatarsals are not useful in distinguishing among hominoids. Further studies should concentrate on measuring other important qualitative and quantitative differences in the shape of the metatarsal head of hominoids that are not reflected in simple geometric reconstructions of the articulation, and gathering more forefoot kinematic data on great apes to better understand differences in range of motion and loading patterns of the metatarsals. Am J Phys Anthropol 143:198-207, 2010. [c] 2010 Wiley-Liss, Inc. KEY WORDS forefoot; metatarsophalangeal joint; australopithecine locomotion; cross-sectional geometry; metatarsus DOI 10.1002/ajpa.21306

This study investigates the relationships between lower limb robusticity and mobility in a Neolithic sample (LIG) from Italy (6th millennium BP). This study tests the hypothesis that the high femoral robusticity previously observed in the LIG sample is a consequence of the subsistence strategy (i.e., high mobility on uneven terrain) practiced by LIG. Cross-sectional geometric properties of the femur and tibia at midshaft of LIG (eight males and eight females) were collected and results compared to Late Upper Paleolithic (12 males, five females), Mesolithic (24 males, 8 females), and Eneolithic (28 males, 17 females) samples from other sites throughout Europe. The results show that the LIG sample does not show the reduction of lower limb robusticity that is characteristic of the Eneolithic sample, but rather that the LIG sample is most similar to the earlier, highly mobile, populations. This high level of robusticity in the LIG sample could reflect both their pastoral subsistence strategy combined with a rugged environment, as well as their earlier temporal position within the Neolithic. The results of this study further point to significant variation in male-female mobility patterns in the region, also possibly related to pastoral behavioral patterns. KEY WORDS tibia; femur; biomechanics; mobility; European Neolithic

The purpose of this article is to investigate temporal shifts in skeletal robusticity to infer behavioral changes in two populations (Neolithic, NEOL and Medieval, MED) settled in the same geographic area but involved in different subsistence economies (pastoralism and coastal resources exploitation). This comparison allows us to test the hypothesis that occupational stress and mobility in the same environment produce predictable changes in the robusticity of both upper and lower limbs. Results show a lower degree of humeral robusticity and a similar degree of humeral asymmetry in the two sexes in the MED population. These results are consistent with the relatively less stressful subsistence economy documented in the MED population relative to that of the NEOL. Lower limb results suggest that femoral robusticity does not correlate directly with the level of logistical mobility, but is instead due to the summation of several diverse factors that place biomechanical loads on the hindlimb, particularly unevenness of the terrain. However, female femoral gracility seems to indicate that below a certain 'threshold' of mobility, i.e., movement over the natural terrain, terrain conformation is no longer the main contributing factor to femoral robusticity. The femoral shape index [I.sub.x]/[I.sub.y] declines through time, particularly in males. This agrees with the expected mobility of the samples based on archaeological and historical data, providing further evidence on the reliability of this index in inferring terrestrial mobility. KEY WORDS cross-sectional geometry; humerus; femur; mobility

This paper investigates the changes in upper and lower limb robusticity and activity patterns that accompanied the transition to a Neolithic subsistence in western Liguria (Italy). Diaphyseal robusticity measures were obtained from cross-sectional geometric properties of the humerus and femur in a sample of 16 individuals (eight males and eight females) dated to about 6,000-5,500 BP. Comparisons with European Late Upper Paleolithics (LUP) indicate increased humeral robusticity in Neolithic Ligurian (NEOL) males, but not in females, with a significant reduction in right-left differences in both sexes. Sexual dimorphism in robusticity increases in upper and lower limb bones. Regarding the femur, while all female indicators of bending strength decrease steadily through time, values for NEOL males approach those of LUP. This suggests high, and unexpected, levels of mechanical stress for NEOL males, probably reflecting the effects of the mountainous terrain on lower limb remodeling. Comparisons between NEOL males and a small sample of LUP hunter-gatherers from the same area support this interpretation. In conclusion, cross-sectional geometry data indicate that the transition to Neolithic economies in western Liguria did not reduce functional requirements in males, and suggest a marked sexual division of labor involving a more symmetrical use of the upper limb, and different male-female levels of locomotory stress. When articulated with archaeological, faunal, paleopathological, and ethnographic evidence, these results support the hypothesis of repetitive, bimanual use of axes tied to pastoral activities in males, and of more sedentary tasks linked to agriculture in females. KEY WORDS cross-sectional geometry; bioarchaeology; femur; humerus; mobility

This paper reports on a case of massive hyperostotic alterations observed in the skeleton of an adult woman from the necropolis of Montescaglioso Belvedere (Basilicata, Southern Italy) attributed to the Enotrian culture and dated to the 6th century BC. Hyperostotic changes involve joints, the vertebral column, and the lower limbs. In particular, the large flowing ossification in both the thoracic (T6-T10) and lumbar (L2-L5) tracts, the sacralization of L5, accompanied by sacroiliac fusion on the left side, and the proliferative bone production on both the metaphyseal portion of the left tibia and the left third metatarsal are described. The vertebral antero-lateral ossification and the sacroiliac fusion support a diagnosis of diffuse idiopathic skeletal hyperostosis (DISH), while the flowing bone formation on the lower limbs supports a diagnosis of melorheostosis. The pathological conditions described here were already described in the literature, but this is the first reported case of the coexistence of DISH and the very rare melorheostosis. Furthermore, the skeleton from Montescaglioso Belvedere represents the first case of this disease described for ancient Europe, therefore adding a valuable contribution to the reconstruction of the antiquity and distribution of skeletal dysplasias. KEY WORDS sclerosing bone dysplasia; diffuse idiopathic skeletal hyperostosis; Magna Graecia

Objectives: Long bone variations during growth are susceptible to the combined action of nutritional, hormonal, and genetic factors that may modulate the mechanical forces acting upon growing individuals as they progressively acquire a mature gait. In this work, we explore diaphyseal length and breadth variations of tibia and fibula during ontogeny (a) to test the presence of changes in relation to early toddling, and (b) to further our understanding of developmental patterns in relation to sex. Materials and Methods: Lengths, breadths, and indices were analyzed on right and left leg bones of 68 subadult individuals (Human Identified Skeletal Collection of the University of Bologna, Italy). Analyses included intersex and age classes (1, 0–1 year; 2, 1.1–3 years; 3, 3.1–6 years) comparisons, linear regressions with age and assessment of correlation among tibial and fibular measurements, as well as principal component analysis. Results: A significant difference emerged among age class 1 and the others. Age class 1 and 3 differ between them, while age class 2 overlaps with the others. No sex dimorphism was detected. All measurements were strongly correlated with age. Tibial and fibular measurements correlated with each other. Conclusions: Our results relate the progressive emergence of toddling attempts in growing individuals at the end of the first year of age. No significant sex differences were found, suggesting that tibial and fibula growth might diverge between sexes in later childhood. We provide quantitative data regarding tibial and fibular linear growth and its timing in a modern documented osteological sample from Italy. [ABSTRACT FROM AUTHOR]

This project aims to test whether geometric morphometric (GM) and trabecular analyses may be useful tools in identifying talar characteristics related to hypochondroplasia. We quantified the external and internal talar morphology of a hypochondroplasic dwarf (T17) from Modena (northern Italy) dated to the sixth century AD. External talar morphology of T17 was compared with a broad sample of modern human tali (n = 159) using GM methods. Additionally, a subsample of these tali (n = 41) was used to investigate whole talar trabecular changes in T17. Our results show that GM and trabecular analyses identify a combination of traits linked to the dwarfing disorder of hypochondroplasia. These traits include decreased scaled talar dimensions compared with normal‐sized individuals, presence of an accessory antero‐lateral talar facet, high bone volume fraction, and high anisotropy values throughout the entire talus. In our case study, hypochondroplasia does not appear to substantially modify external talar morphology probably due to the fast growth of the talus. We suggest that small talar dimensions are associated with hypochondroplasia. An antero‐lateral talar facet may result from the talus and calcaneus coalition (i.e., talocalcaneal abnormal bridging) possibly related to an everted foot posture that was limited by overgrowth of the fibula. We suggest that high talar trabecular density and strut orientation provide insights into pathological development of the trabecular plates in T17. Finally, our study suggests that high talar trabecular density and strut orientation, and small talar dimensions, may be added as possible concomitant talar hallmarks for hypochondroplasia. [ABSTRACT FROM AUTHOR]